Steam boiler



July 5 1927.

J. R, MAGARVEY- TNESSES Patented July 5, 1927.

PATENT oFFicE.

'JOHN MAGARVEY, OF SGHENECTADY, NEW YORK.

, STEAM BOILER.

Application filed August 27, 1926. Serial No. 131,875.

My invention relates to steam boilers of the tubular type, and its object is to provide means for effectingthe connection of the tube or flue sheets to the firebox or combustion chamber, whereby the deterioration of the sheets, due to exposure to the high temperatures of combustion may be substantially overcome.

The improvement claimed is hereinafter fully set forth.

In the present practice of boiler construction, the manner of Hanging the tube sheets I is such that the heads of the connecting rivets are exposed to the direct heat of the fire, on the rear tube sheet, and to that of the smoke box, on the front tube sheet, the effect of which is to cause their unduly rapid deterioration. My invention is designed to minimize this effect, without involving increased cost of construction, or structural complication.

In the accompanying drawing: Figure l is a vertical longitudinal central section through a locomotive boiler, having a combustion chamber, illustrating an embodiment of the invention; Fig. 2, a partial similar section, through a locomotive boiler, not having a combustion chamber, in which the invention is applied; Fig. 3, a half transverse section, through the same, on the line a a of Fig. 2; and. Fig. 4, a transverse section, on an enlarged scale, through the tirebox tube sheet, on the line b 7) of. Fig. 2.

In the practice of my invention, referring d-escriptively to the specific embodiment thereof which is herein exemplified, and first to Fig. 1, the boiler comprises the usual shell or waist, 1, firebox, 2, combustion chamber. 3, smoke box, 4, rear tube sheet,

which extends inwardly, that is, towards the front of the boiler, and is secured to the crown sheet, 2, and combustion chamber sheet, 2 by aseam of rivets, 5 It will be seen that, under this construction, the heads of the rivets, 6 and 5 are completely protected from the direct access of the heat of the smoke box and the firebox, and that a correspondingexemption from the deterioration resultant upon such direct access of heat, isattained, without increase of structural cost or of the number of connecting rivets.

The application of the invention in a bo ler which is not fitted with a. combustion chamber, as iliustrated in Figs. 2, 3 and 4:,

differs from that before described, in the particular that the flange, 7 of the rear tube sheet, is not inwardly turned, continuously, on the tube sheet, 7, but extends inwardly only from the crown sheet, 2 to the point at which the connection of the tube sheet to the shell sheet commences. From this point to the lower end of the tube sheet, the flange is turned rearwardly. In order to ensure a tight joint, welding material, 7, is applied on the line upon which the flange is turned in opposite directions.

The invention presents the substantial practical advantages that the riveted seams.

being on the water sides of the tube sheets, 7

the cracking of the sheets on the nre side, due to vertical expansion and other cause. will be avoided, and that this result is attained without additional cost of manufacof a plurality of fire tubes; a front tube sheet, connected to the forward ends of Said tubes; a rear tube sheet, connected to the rear ends of said tubes, and having a flange turned inwardly, that 1s, on the water sure ,thereof, from its top to the commencing A point or 1ts connection to the boiler shell.

and turned in reverse direction for the remainder of its depth; and-rivets, connectmg said tube sheets to the boiler structure.

JOHN R. MAGARVEY. 

